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<a name="callable_traits"></a>CallableTraits</h2></div>
<div><div class="authorgroup"><div class="author"><h3 class="author">
<span class="firstname">Barrett</span> <span class="surname">Adair</span>
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<div><p class="copyright">Copyright © 2016-2021 Barrett Adair</p></div>
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<a name="callable_traits.legal"></a><p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE.md or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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<p><b>Table of Contents</b></p>
<dl class="toc">
<dt><span class="section"><a href="index.html#callable_traits.introduction">Overview</a></span></dt>
<dd><dl>
<dt><span class="section"><a href="index.html#callable_traits.introduction.motivation">Motivation</a></span></dt>
<dt><span class="section"><a href="index.html#callable_traits.introduction.boost_function_types">Regarding
      <code class="literal">Boost.FunctionTypes</code></a></span></dt>
<dt><span class="section"><a href="index.html#callable_traits.introduction.compatibility">Compatibility</a></span></dt>
</dl></dd>
<dt><span class="section"><a href="callable_traits/reference.html">Reference Documentation</a></span></dt>
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<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_add_member_const">add_member_const</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_add_member_cv">add_member_cv</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_add_member_lvalue_reference">add_member_lvalue_reference</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_add_member_rvalue_reference">add_member_rvalue_reference</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_add_member_volatile">add_member_volatile</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_add_noexcept">add_noexcept</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_add_transaction_safe">add_transaction_safe</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_add_varargs">add_varargs</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_apply_member_pointer">apply_member_pointer</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_apply_return">apply_return</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_args">args</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_class_of">class_of</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_function_type">function_type</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_has_member_qualifiers">has_member_qualifiers</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_has_varargs">has_varargs</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_has_void_return">has_void_return</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_const_member">is_const_member</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_cv_member">is_cv_member</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_invocable">is_invocable</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_lvalue_reference_member">is_lvalue_reference_member</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_reference_member">is_reference_member</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_rvalue_reference_member">is_rvalue_reference_member</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_noexcept">is_noexcept</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_transaction_safe">is_transaction_safe</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_is_volatile_member">is_volatile_member</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_qualified_class_of">qualified_class_of</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_const">remove_member_const</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_cv">remove_member_cv</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_reference">remove_member_reference</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_volatile">remove_member_volatile</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_remove_noexcept">remove_noexcept</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_remove_transaction_safe">remove_transaction_safe</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_remove_varargs">remove_varargs</a></span></dt>
<dt><span class="section"><a href="callable_traits/reference.html#callable_traits.reference.ref_return_type">return_type</a></span></dt>
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<dt><span class="section"><a href="callable_traits/faq.html">FAQ</a></span></dt>
<dt><span class="section"><a href="callable_traits/building.html">Building the test suite</a></span></dt>
<dt><span class="section"><a href="callable_traits/contact.html">Contact</a></span></dt>
<dt><span class="section"><a href="callable_traits/acknowledgements.html">Acknowledgements</a></span></dt>
</dl>
</div>
<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="callable_traits.introduction"></a><a class="link" href="index.html#callable_traits.introduction" title="Overview">Overview</a>
</h2></div></div></div>
<div class="toc"><dl class="toc">
<dt><span class="section"><a href="index.html#callable_traits.introduction.motivation">Motivation</a></span></dt>
<dt><span class="section"><a href="index.html#callable_traits.introduction.boost_function_types">Regarding
      <code class="literal">Boost.FunctionTypes</code></a></span></dt>
<dt><span class="section"><a href="index.html#callable_traits.introduction.compatibility">Compatibility</a></span></dt>
</dl></div>
<p>
      <code class="literal">Boost.CallableTraits</code> is a C++11 header-only library for
      the inspection, synthesis, and decomposition of callable types. <code class="literal">Boost.CallableTraits</code>
      aims to be the "complete type manipulation facility for function types"
      mentioned in the final paragraph of C++17 proposal <a href="http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2015/p0172r0.html" target="_top">p0172</a>,
      and removes the need for template specializations for different function signatures.
      C++17 <code class="computeroutput"><span class="keyword">noexcept</span></code> and the Transactional
      Memory TS are also supported if available.
    </p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">type_traits</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">tuple</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">callable_traits</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>

<span class="keyword">namespace</span> <span class="identifier">ct</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">callable_traits</span><span class="special">;</span>

<span class="comment">// This function template helps keep our example code neat</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">A</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">B</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">assert_same</span><span class="special">(){</span> <span class="keyword">static_assert</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">is_same</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span> <span class="identifier">B</span><span class="special">&gt;::</span><span class="identifier">value</span><span class="special">,</span> <span class="string">""</span><span class="special">);</span> <span class="special">}</span>

<span class="comment">// foo is a function object</span>
<span class="keyword">struct</span> <span class="identifier">foo</span> <span class="special">{</span>
    <span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">char</span><span class="special">,</span> <span class="keyword">float</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">{}</span>
<span class="special">};</span>

<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> <span class="special">{</span>

    <span class="comment">// Use args_t to retrieve a parameter list as a std::tuple:</span>
    <span class="identifier">assert_same</span><span class="special">&lt;</span>
        <span class="identifier">ct</span><span class="special">::</span><span class="identifier">args_t</span><span class="special">&lt;</span><span class="identifier">foo</span><span class="special">&gt;,</span>
        <span class="identifier">std</span><span class="special">::</span><span class="identifier">tuple</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">char</span><span class="special">,</span> <span class="keyword">float</span><span class="special">&gt;</span>
    <span class="special">&gt;();</span>

    <span class="comment">// has_void_return lets us perform a quick check for a void return type</span>
    <span class="keyword">static_assert</span><span class="special">(</span><span class="identifier">ct</span><span class="special">::</span><span class="identifier">has_void_return</span><span class="special">&lt;</span><span class="identifier">foo</span><span class="special">&gt;::</span><span class="identifier">value</span><span class="special">,</span> <span class="string">""</span><span class="special">);</span>

    <span class="comment">// Detect C-style variadics (ellipses) in a signature (e.g. printf)</span>
    <span class="keyword">static_assert</span><span class="special">(!</span><span class="identifier">ct</span><span class="special">::</span><span class="identifier">has_varargs</span><span class="special">&lt;</span><span class="identifier">foo</span><span class="special">&gt;::</span><span class="identifier">value</span><span class="special">,</span> <span class="string">""</span><span class="special">);</span>

    <span class="comment">// pmf is a pointer-to-member function: void (foo::*)(int, char, float) const</span>
    <span class="keyword">using</span> <span class="identifier">pmf</span> <span class="special">=</span> <span class="keyword">decltype</span><span class="special">(&amp;</span><span class="identifier">foo</span><span class="special">::</span><span class="keyword">operator</span><span class="special">());</span>

    <span class="comment">// remove_member_const_t lets you remove the const member qualifier</span>
    <span class="identifier">assert_same</span><span class="special">&lt;</span>
        <span class="identifier">ct</span><span class="special">::</span><span class="identifier">remove_member_const_t</span><span class="special">&lt;</span><span class="identifier">pmf</span><span class="special">&gt;,</span>
        <span class="keyword">void</span> <span class="special">(</span><span class="identifier">foo</span><span class="special">::*)(</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">char</span><span class="special">,</span> <span class="keyword">float</span><span class="special">)</span> <span class="comment">/*no const!*/</span>
    <span class="special">&gt;();</span>

    <span class="comment">// Conversely, add_member_const_t adds a const member qualifier</span>
    <span class="identifier">assert_same</span><span class="special">&lt;</span>
        <span class="identifier">pmf</span><span class="special">,</span>
        <span class="identifier">ct</span><span class="special">::</span><span class="identifier">add_member_const_t</span><span class="special">&lt;</span><span class="keyword">void</span> <span class="special">(</span><span class="identifier">foo</span><span class="special">::*)(</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">char</span><span class="special">,</span> <span class="keyword">float</span><span class="special">)&gt;</span>
    <span class="special">&gt;();</span>

    <span class="comment">// is_const_member_v checks for the presence of member const</span>
    <span class="keyword">static_assert</span><span class="special">(</span><span class="identifier">ct</span><span class="special">::</span><span class="identifier">is_const_member</span><span class="special">&lt;</span><span class="identifier">pmf</span><span class="special">&gt;::</span><span class="identifier">value</span><span class="special">,</span> <span class="string">""</span><span class="special">);</span>
<span class="special">}</span>
</pre>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="callable_traits.introduction.motivation"></a><a class="link" href="index.html#callable_traits.introduction.motivation" title="Motivation">Motivation</a>
</h3></div></div></div>
<div class="blockquote"><blockquote class="blockquote">
<p>
          <span class="bold"><strong><span class="emphasis"><em><span class="quote">“<span class="quote">Don't try to write helper code to
          detect PMFs/PMDs and dispatch on them -- it is an <span class="underline">absolute
          nightmare</span>. PMF types are the worst types by far in the core
          language.</span>”</span></em></span></strong></span>
        </p>
<p>
          -- Stephan T. Lavavej, CppCon 2015, <a href="https://www.youtube.com/watch?v=zt7ThwVfap0&amp;t=11m40s" target="_top">"functional:
          What's New, And Proper Usage"</a>
        </p>
</blockquote></div>
<p>
        Consider for a moment the code below, which defines all 48 template specializations
        necessary to specialize for every valid function type in pure C++17:
      </p>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">;</span>

<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="special">&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="special">&amp;&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="special">&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="special">&amp;&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">volatile</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">volatile</span> <span class="special">&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">volatile</span> <span class="special">&amp;&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="special">&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="special">&amp;&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="special">&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="special">&amp;&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="special">&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="special">&amp;&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">volatile</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">volatile</span> <span class="special">&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">volatile</span> <span class="special">&amp;&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="special">&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="special">&amp;&amp;&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="special">&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="special">&amp;&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="special">&amp;&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">volatile</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">volatile</span> <span class="special">&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">volatile</span> <span class="special">&amp;&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="special">&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="special">&amp;&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="special">&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="special">&amp;&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="special">&amp;&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">volatile</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">volatile</span> <span class="special">&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">volatile</span> <span class="special">&amp;&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="special">&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">Return</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">foo</span><span class="special">&lt;</span><span class="identifier">Return</span><span class="special">(</span><span class="identifier">Args</span><span class="special">...,</span> <span class="special">...)</span> <span class="keyword">const</span> <span class="keyword">volatile</span> <span class="special">&amp;&amp;</span> <span class="keyword">noexcept</span><span class="special">&gt;</span> <span class="special">{};</span>
</pre>
<p>
        Things get even more complicated with member function pointers, function
        pointers, function references, function objects, and <code class="computeroutput"><span class="identifier">transaction_safe</span></code>.
      </p>
<p>
        Granted, use cases for such obscure specializations are vitually nonexistent
        in run-of-the-mill application codebases. Even in library code, these are
        exceedingly rare. However, there are a handful of metaprogramming scenarios
        that can only be solved with this kind of template "spam". Writing,
        testing, and maintaining such code is tedious and costly.
      </p>
<p>
        <code class="literal">Boost.CallableTraits</code> offers a final and decisive library-level
        solution to this problem, and removes the need for these specializations
        entirely (platform-specific calling conventions notwithstanding).
      </p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="callable_traits.introduction.boost_function_types"></a><a class="link" href="index.html#callable_traits.introduction.boost_function_types" title="Regarding Boost.FunctionTypes">Regarding
      <code class="literal">Boost.FunctionTypes</code></a>
</h3></div></div></div>
<p>
        The features in <code class="literal">Boost.CallableTraits</code> largely overlap with
        <a href="http://www.boost.org/doc/libs/1_61_0/libs/function_types/doc/html/index.html" target="_top"><code class="literal">Boost.FunctionTypes</code></a>.
        Here are some reasons why you might prefer <code class="literal">Boost.CallableTraits</code>:
      </p>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem">
            <code class="literal">Boost.FunctionTypes</code> is tightly coupled to <a href="http://www.boost.org/doc/libs/1_64_0/libs/mpl/doc/index.html" target="_top"><code class="literal">Boost.MPL</code></a>
            sequences, while <code class="literal">Boost.CallableTraits</code> has no dependencies
            other than the standard library.
          </li>
<li class="listitem">
            <code class="literal">Boost.CallableTraits</code> targets C++11 and later:
            <div class="orderedlist"><ol class="orderedlist" type="a">
<li class="listitem">
                  <code class="literal">Boost.CallableTraits</code> treats function objects/lambdas
                  as first-class citizens.
                </li>
<li class="listitem">
                  <code class="literal">Boost.CallableTraits</code> supports lvalue/rvalue
                  reference member qualifiers.
                </li>
<li class="listitem">
                  <code class="literal">Boost.CallableTraits</code> supports <code class="computeroutput"><span class="keyword">noexcept</span></code> and <code class="computeroutput"><span class="identifier">transaction_safe</span></code>.
                </li>
</ol></div>
          </li>
<li class="listitem">
            <code class="literal">Boost.FunctionTypes</code> does not attempt to factor all
            callable types into a unified, <a href="http://en.cppreference.com/w/cpp/utility/functional/invoke" target="_top"><code class="literal"><span class="emphasis"><em>INVOKE</em></span></code></a>-aware
            interface.
          </li>
<li class="listitem">
            <code class="literal">Boost.FunctionTypes</code> relies heavily on "tag"
            types, while <code class="literal">Boost.CallableTraits</code> follows the style
            of &lt;type_traits&gt; instead. Supporting C++11 and later in <code class="literal">Boost.FunctionTypes</code>
            would have required significant proliferation of these tags.
          </li>
</ol></div>
<p>
        For example, here is how to remove member <code class="computeroutput"><span class="keyword">const</span></code>
        from a member function pointer type in the <code class="literal">Boost.FunctionTypes</code>
        library:
      </p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">type_traits</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">function_types</span><span class="special">/</span><span class="identifier">components</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">function_types</span><span class="special">/</span><span class="identifier">member_function_pointer</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>

<span class="keyword">struct</span> <span class="identifier">foo</span> <span class="special">{</span>
    <span class="keyword">void</span> <span class="identifier">bar</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">{}</span>
<span class="special">};</span>

<span class="keyword">using</span> <span class="identifier">const_removed</span> <span class="special">=</span> <span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">function_types</span><span class="special">::</span><span class="identifier">member_function_pointer</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">function_types</span><span class="special">::</span><span class="identifier">components</span><span class="special">&lt;</span><span class="keyword">decltype</span><span class="special">(&amp;</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">)&gt;::</span><span class="identifier">types</span><span class="special">,</span>
    <span class="identifier">boost</span><span class="special">::</span><span class="identifier">function_types</span><span class="special">::</span><span class="identifier">non_const</span><span class="special">&gt;::</span><span class="identifier">type</span><span class="special">;</span>

<span class="keyword">static_assert</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">is_same</span><span class="special">&lt;</span><span class="identifier">const_removed</span><span class="special">,</span> <span class="keyword">void</span><span class="special">(</span><span class="identifier">foo</span><span class="special">::*)()&gt;::</span><span class="identifier">value</span><span class="special">,</span> <span class="string">""</span><span class="special">);</span>

<span class="keyword">int</span> <span class="identifier">main</span><span class="special">(){}</span>
</pre>
<p>
        <code class="literal">Boost.CallableTraits</code> makes this easier:
      </p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">type_traits</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">callable_traits</span><span class="special">/</span><span class="identifier">remove_member_const</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>

<span class="keyword">struct</span> <span class="identifier">foo</span> <span class="special">{</span>
        <span class="keyword">void</span> <span class="identifier">bar</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">{}</span>
<span class="special">};</span>

<span class="keyword">using</span> <span class="identifier">const_removed</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">callable_traits</span><span class="special">::</span><span class="identifier">remove_member_const_t</span><span class="special">&lt;</span><span class="keyword">decltype</span><span class="special">(&amp;</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">)&gt;;</span>

<span class="keyword">static_assert</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">is_same</span><span class="special">&lt;</span><span class="identifier">const_removed</span><span class="special">,</span> <span class="keyword">void</span><span class="special">(</span><span class="identifier">foo</span><span class="special">::*)()&gt;::</span><span class="identifier">value</span><span class="special">,</span> <span class="string">""</span><span class="special">);</span>

<span class="keyword">int</span> <span class="identifier">main</span><span class="special">(){}</span>
</pre>
<p>
        The <code class="literal">Boost.FunctionTypes</code> library includes an excellent
        <a href="http://www.boost.org/doc/libs/1_64_0/libs/function_types/example/interface_example.cpp" target="_top">example</a>
        for generating type-erased interfaces (implementation <a href="http://www.boost.org/doc/libs/1_64_0/libs/function_types/example/interface.hpp" target="_top">here</a>).
        This example was <a href="https://github.com/badair/eraserface/blob/master/include/eraserface/eraserface.hpp" target="_top">re-implemented</a>
        using <code class="literal">Boost.CallableTraits</code> to yield a <a href="https://github.com/badair/eraserface/blob/master/example/basic_example.cpp" target="_top">slightly
        more intuitive interface</a>.
      </p>
<p>
        <code class="literal">Boost.FunctionTypes</code> is a fine library, but its interface
        left room for improvement.
      </p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="callable_traits.introduction.compatibility"></a><a class="link" href="index.html#callable_traits.introduction.compatibility" title="Compatibility">Compatibility</a>
</h3></div></div></div>
<p>
        <code class="literal">Boost.CallableTraits</code> supports on GCC 4.7.4+, Clang 3.5.2+,
        XCode 6.4+, and Visual Studio 2015+. The Intel C++ Compiler is not officially
        supported, although the 2017 version for Linux does pass a handful of test
        cases.
      </p>
<div class="table">
<a name="callable_traits.introduction.compatibility.gcc_support"></a><p class="title"><b>Table 1. GCC Support</b></p>
<div class="table-contents"><table class="table" summary="GCC Support">
<colgroup>
<col>
<col>
<col>
<col>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  feature
                </p>
              </th>
<th>
                <p>
                  GCC 7.3.0 and later
                </p>
              </th>
<th>
                <p>
                  GCC 6.3.0
                </p>
              </th>
<th>
                <p>
                  GCC 5.4.0
                </p>
              </th>
<th>
                <p>
                  GCC 4.9.2
                </p>
              </th>
<th>
                <p>
                  GCC 4.8.2
                </p>
              </th>
<th>
                <p>
                  GCC 4.7.4
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_const" title="add_member_const"><code class="literal">add_member_const</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_cv" title="add_member_cv"><code class="literal">add_member_cv</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_lvalue_reference" title="add_member_lvalue_reference"><code class="literal">add_member_lvalue_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_rvalue_reference" title="add_member_rvalue_reference"><code class="literal">add_member_rvalue_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_volatile" title="add_member_volatile"><code class="literal">add_member_volatile</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_noexcept" title="add_noexcept"><code class="literal">add_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_transaction_safe" title="add_transaction_safe"><code class="literal">add_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++17</span> (requires -fgnu-tm)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++17</span> (requires -fgnu-tm)
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_varargs" title="add_varargs"><code class="literal">add_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_apply_member_pointer" title="apply_member_pointer"><code class="literal">apply_member_pointer</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_apply_return" title="apply_return"><code class="literal">apply_return</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_args" title="args"><code class="literal">args</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_class_of" title="class_of"><code class="literal">class_of</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_function_type" title="function_type"><code class="literal">function_type</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_member_qualifiers" title="has_member_qualifiers"><code class="literal">has_member_qualifiers</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_varargs" title="has_varargs"><code class="literal">has_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_void_return" title="has_void_return"><code class="literal">has_void_return</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_const_member" title="is_const_member"><code class="literal">is_const_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_cv_member" title="is_cv_member"><code class="literal">is_cv_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_invocable" title="is_invocable"><code class="literal">is_invocable</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  unknown
                </p>
              </td>
<td>
                <p>
                  unknown
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_lvalue_reference_member" title="is_lvalue_reference_member"><code class="literal">is_lvalue_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_noexcept" title="is_noexcept"><code class="literal">is_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_reference_member" title="is_reference_member"><code class="literal">is_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_rvalue_reference_member" title="is_rvalue_reference_member"><code class="literal">is_rvalue_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_transaction_safe" title="is_transaction_safe"><code class="literal">is_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++17</span> (requires -fgnu-tm)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++17</span> (requires -fgnu-tm)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_volatile_member" title="is_volatile_member"><code class="literal">is_volatile_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_qualified_class_of" title="qualified_class_of"><code class="literal">qualified_class_of</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_const" title="remove_member_const"><code class="literal">remove_member_const</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_cv" title="remove_member_cv"><code class="literal">remove_member_cv</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_reference" title="remove_member_reference"><code class="literal">remove_member_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_volatile" title="remove_member_volatile"><code class="literal">remove_member_volatile</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no abominables)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_noexcept" title="remove_noexcept"><code class="literal">remove_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_transaction_safe" title="remove_transaction_safe"><code class="literal">remove_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++17</span> (requires -fgnu-tm)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++17</span> (requires -fgnu-tm)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_varargs" title="remove_varargs"><code class="literal">remove_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_return_type" title="return_type"><code class="literal">return_type</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break"><div class="table">
<a name="callable_traits.introduction.compatibility.llvm_clang_support"></a><p class="title"><b>Table 2. LLVM/Clang Support</b></p>
<div class="table-contents"><table class="table" summary="LLVM/Clang Support">
<colgroup>
<col>
<col>
<col>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  feature
                </p>
              </th>
<th>
                <p>
                  Clang 4.0.0 and later
                </p>
              </th>
<th>
                <p>
                  Clang 3.8.0
                </p>
              </th>
<th>
                <p>
                  Clang 3.7.1
                </p>
              </th>
<th>
                <p>
                  Clang 3.6.2
                </p>
              </th>
<th>
                <p>
                  Clang 3.5.2
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_const" title="add_member_const"><code class="literal">add_member_const</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_cv" title="add_member_cv"><code class="literal">add_member_cv</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_lvalue_reference" title="add_member_lvalue_reference"><code class="literal">add_member_lvalue_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_rvalue_reference" title="add_member_rvalue_reference"><code class="literal">add_member_rvalue_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_volatile" title="add_member_volatile"><code class="literal">add_member_volatile</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_noexcept" title="add_noexcept"><code class="literal">add_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_transaction_safe" title="add_transaction_safe"><code class="literal">add_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_varargs" title="add_varargs"><code class="literal">add_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_apply_member_pointer" title="apply_member_pointer"><code class="literal">apply_member_pointer</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_apply_return" title="apply_return"><code class="literal">apply_return</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_args" title="args"><code class="literal">args</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_class_of" title="class_of"><code class="literal">class_of</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_function_type" title="function_type"><code class="literal">function_type</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_member_qualifiers" title="has_member_qualifiers"><code class="literal">has_member_qualifiers</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_varargs" title="has_varargs"><code class="literal">has_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_void_return" title="has_void_return"><code class="literal">has_void_return</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_const_member" title="is_const_member"><code class="literal">is_const_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_cv_member" title="is_cv_member"><code class="literal">is_cv_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_invocable" title="is_invocable"><code class="literal">is_invocable</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_lvalue_reference_member" title="is_lvalue_reference_member"><code class="literal">is_lvalue_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_noexcept" title="is_noexcept"><code class="literal">is_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_reference_member" title="is_reference_member"><code class="literal">is_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_rvalue_reference_member" title="is_rvalue_reference_member"><code class="literal">is_rvalue_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_transaction_safe" title="is_transaction_safe"><code class="literal">is_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_volatile_member" title="is_volatile_member"><code class="literal">is_volatile_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_qualified_class_of" title="qualified_class_of"><code class="literal">qualified_class_of</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_const" title="remove_member_const"><code class="literal">remove_member_const</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_cv" title="remove_member_cv"><code class="literal">remove_member_cv</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_reference" title="remove_member_reference"><code class="literal">remove_member_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_volatile" title="remove_member_volatile"><code class="literal">remove_member_volatile</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_noexcept" title="remove_noexcept"><code class="literal">remove_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++17</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_transaction_safe" title="remove_transaction_safe"><code class="literal">remove_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_varargs" title="remove_varargs"><code class="literal">remove_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_return_type" title="return_type"><code class="literal">return_type</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break"><div class="table">
<a name="callable_traits.introduction.compatibility.xcode_appleclang_support"></a><p class="title"><b>Table 3. XCode/AppleClang Support</b></p>
<div class="table-contents"><table class="table" summary="XCode/AppleClang Support">
<colgroup>
<col>
<col>
<col>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  feature
                </p>
              </th>
<th>
                <p>
                  XCode 8 and later
                </p>
              </th>
<th>
                <p>
                  XCode 7.3
                </p>
              </th>
<th>
                <p>
                  XCode 7.2
                </p>
              </th>
<th>
                <p>
                  XCode 7.1
                </p>
              </th>
<th>
                <p>
                  XCode 6.4
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_const" title="add_member_const"><code class="literal">add_member_const</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_cv" title="add_member_cv"><code class="literal">add_member_cv</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_lvalue_reference" title="add_member_lvalue_reference"><code class="literal">add_member_lvalue_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_rvalue_reference" title="add_member_rvalue_reference"><code class="literal">add_member_rvalue_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_volatile" title="add_member_volatile"><code class="literal">add_member_volatile</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_noexcept" title="add_noexcept"><code class="literal">add_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  unknown
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_transaction_safe" title="add_transaction_safe"><code class="literal">add_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  unknown
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_varargs" title="add_varargs"><code class="literal">add_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_apply_member_pointer" title="apply_member_pointer"><code class="literal">apply_member_pointer</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_apply_return" title="apply_return"><code class="literal">apply_return</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_args" title="args"><code class="literal">args</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_class_of" title="class_of"><code class="literal">class_of</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_function_type" title="function_type"><code class="literal">function_type</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_member_qualifiers" title="has_member_qualifiers"><code class="literal">has_member_qualifiers</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_varargs" title="has_varargs"><code class="literal">has_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_void_return" title="has_void_return"><code class="literal">has_void_return</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_const_member" title="is_const_member"><code class="literal">is_const_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_cv_member" title="is_cv_member"><code class="literal">is_cv_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_invocable" title="is_invocable"><code class="literal">is_invocable</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_lvalue_reference_member" title="is_lvalue_reference_member"><code class="literal">is_lvalue_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_noexcept" title="is_noexcept"><code class="literal">is_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  unknown
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_reference_member" title="is_reference_member"><code class="literal">is_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_rvalue_reference_member" title="is_rvalue_reference_member"><code class="literal">is_rvalue_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_transaction_safe" title="is_transaction_safe"><code class="literal">is_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  unknown
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_volatile_member" title="is_volatile_member"><code class="literal">is_volatile_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_qualified_class_of" title="qualified_class_of"><code class="literal">qualified_class_of</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_const" title="remove_member_const"><code class="literal">remove_member_const</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_cv" title="remove_member_cv"><code class="literal">remove_member_cv</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_reference" title="remove_member_reference"><code class="literal">remove_member_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_volatile" title="remove_member_volatile"><code class="literal">remove_member_volatile</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_noexcept" title="remove_noexcept"><code class="literal">remove_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  unknown
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_transaction_safe" title="remove_transaction_safe"><code class="literal">remove_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  unknown
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_varargs" title="remove_varargs"><code class="literal">remove_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_return_type" title="return_type"><code class="literal">return_type</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break"><div class="table">
<a name="callable_traits.introduction.compatibility.visual_studio_support"></a><p class="title"><b>Table 4. Visual Studio Support</b></p>
<div class="table-contents"><table class="table" summary="Visual Studio Support">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  feature
                </p>
              </th>
<th>
                <p>
                  MSVC with Visual Studio 2017
                </p>
              </th>
<th>
                <p>
                  MSVC with Visual Studio 2015 (latest update)
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_const" title="add_member_const"><code class="literal">add_member_const</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_cv" title="add_member_cv"><code class="literal">add_member_cv</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_lvalue_reference" title="add_member_lvalue_reference"><code class="literal">add_member_lvalue_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_rvalue_reference" title="add_member_rvalue_reference"><code class="literal">add_member_rvalue_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_member_volatile" title="add_member_volatile"><code class="literal">add_member_volatile</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_noexcept" title="add_noexcept"><code class="literal">add_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_transaction_safe" title="add_transaction_safe"><code class="literal">add_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
<td>
                <p>
                  <span class="red">static_assert fails on instantiation</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_add_varargs" title="add_varargs"><code class="literal">add_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span> (define BOOST_DISABLE_WIN32
                  to disable __cdecl on PMF varargs)
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span> (define BOOST_DISABLE_WIN32
                  to disable __cdecl on PMF varargs)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_apply_member_pointer" title="apply_member_pointer"><code class="literal">apply_member_pointer</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_apply_return" title="apply_return"><code class="literal">apply_return</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_args" title="args"><code class="literal">args</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_class_of" title="class_of"><code class="literal">class_of</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_function_type" title="function_type"><code class="literal">function_type</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_member_qualifiers" title="has_member_qualifiers"><code class="literal">has_member_qualifiers</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_varargs" title="has_varargs"><code class="literal">has_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span> (define BOOST_DISABLE_WIN32
                  to disable __cdecl on PMF varargs)
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span> (define BOOST_DISABLE_WIN32
                  to disable __cdecl on PMF varargs)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_has_void_return" title="has_void_return"><code class="literal">has_void_return</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_const_member" title="is_const_member"><code class="literal">is_const_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_cv_member" title="is_cv_member"><code class="literal">is_cv_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_invocable" title="is_invocable"><code class="literal">is_invocable</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false for functions
                  that are simultaneously ref and cv-qualified due to compiler bug)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_lvalue_reference_member" title="is_lvalue_reference_member"><code class="literal">is_lvalue_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_noexcept" title="is_noexcept"><code class="literal">is_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_reference_member" title="is_reference_member"><code class="literal">is_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_rvalue_reference_member" title="is_rvalue_reference_member"><code class="literal">is_rvalue_reference_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_transaction_safe" title="is_transaction_safe"><code class="literal">is_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (always false)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_is_volatile_member" title="is_volatile_member"><code class="literal">is_volatile_member</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_qualified_class_of" title="qualified_class_of"><code class="literal">qualified_class_of</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_const" title="remove_member_const"><code class="literal">remove_member_const</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_cv" title="remove_member_cv"><code class="literal">remove_member_cv</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_reference" title="remove_member_reference"><code class="literal">remove_member_reference</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_member_volatile" title="remove_member_volatile"><code class="literal">remove_member_volatile</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_noexcept" title="remove_noexcept"><code class="literal">remove_noexcept</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_transaction_safe" title="remove_transaction_safe"><code class="literal">remove_transaction_safe</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
<td>
                <p>
                  <span class="gold">c++11</span> (no effect)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_remove_varargs" title="remove_varargs"><code class="literal">remove_varargs</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span> (define BOOST_DISABLE_WIN32
                  to disable __cdecl on PMF varargs)
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span> (define BOOST_DISABLE_WIN32
                  to disable __cdecl on PMF varargs)
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="callable_traits/reference.html#callable_traits.reference.ref_return_type" title="return_type"><code class="literal">return_type</code></a>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
<td>
                <p>
                  <span class="green">c++11</span>
                </p>
              </td>
</tr>
</tbody>
</table></div>
</div>
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